Let us declare with certitude the obvious: Rep. Anthony Weiner has disgraced his office, and himself, and he needs to quit.

Never mind that he went before the TV cameras yesterday, cried on cue and assumed “responsibility” for a litany of offenses to common decency — including sending lewd messages and revealing photos to young women on Twitter, and then lying about it.

Repeatedly and egregiously.

Because there is a difference between taking rhetorical responsibility for what one has done, and accepting the full consequences of those actions — which in Weiner’s case would require his resignation.

He obliterated his bond of trust with New York’s 9th Congressional District, rendered himself and his office a national laughingstock, used that office to satisfy perverse sexual urges — in the process, laying himself open to blackmail.

House Minority Leader Nancy Pelosi appears to get it: Yesterday she called for an Ethics Committee probe of the mess (and maybe she can get Rep. Charlie Rangel, who has some experience with such things, to show Weiner the ropes).

Yes, the congressman insisted that there’s no need to resign, because “I don’t believe I did anything that violates any law or my oath to my constituents” to uphold the Constitution.

“Nothing about this should reflect on my official duties [or] my record.”

Really?

Let’s put it this way: Any offenses that result in a press conference in which a member of Congress can relevantly be asked “Were you fully erect?” are offenses that disqualify that congressman from public service.

It’s that simple.

“My constituents have to make the determination,” he said.

Which is technically true.

But if Tony Weiner had a shred of personal honor, he’d relieve them of that responsibility.

He won’t, because he is devoid of honor. That was made clear by his weeklong campaign of lies and character assassination meant to deceive his wife of less than a year, his staff, his constituents and the general public — and to vilify Andrew Breitbart, the online journalist who first disclosed the salacious photos and messages.

Breitbart has made mistakes. But he’s scored important scoops, too.

Including this one.

Bottom line: Anthony Weiner betrayed his office and his constituents along with his wife. He has lost whatever respect — and effectiveness — he ever enjoyed as a member of Congress.

Now he’s fit only for cable-TV comedy punch lines, and it’s going to get worse.